Sergeant Darren Kidd of Alexandra said two vehicles, including a passenger van, were involved in the Lindis Pass crash about 25km north of Tarras shortly after 10am.
"It's just an overtaking manoeuvre that's gone wrong.
"Thankfully both parties have reduced their speeds, there's no serious injury."
He said there had been eight occupants in the van and two in the car, all overseas tourists.
Paramedics were checking the occupants on the vehicles.
Emergency crews had a heavy presence on site, including several fire appliances, St John's ambulances and police vehicles from Alexandra, Cromwell and Wānaka.
A stop-go system had been put in place but traffic was now flowing in both directions.
While dark clouds hung over the valley, Sgt Kidd said it had not been raining at the time of the crash.
"It's just a good reminder it's that time of the year conditions are going to get colder.
"Be aware of your surroundings when you're driving."